fix: disconnect signals and config callbacks on destroy

- dock/main.py: off_config_change in destroy()
- switcher/main.py: add destroy() for capture signals + config
- panel/main.py: disconnect fullscreen-changed signal
- notification_center.py: add destroy() for 4 notification signals

src/window/dock/main.py

@@ -176,6 +176,9 @@ class Dock(Window):
     def destroy(self) -> None:
         self._destroyed = True
         self._disconnect_occlusion_signals()
+        from services.config import off_config_change
+
+        off_config_change(self._on_config_change)
 
         if hasattr(self, "canvas") and self.canvas:
             self.canvas.destroy()